I haven't seen such a thread here and it seems to be a good time to start one.
I doubt there is much value in suggesting the pop carols and tunes by all the usual suspects; I reckon that albums that are unusual and not in play everywhere all day and night will be more interesting.
That said, a first list:
1. Paolo Fresu, Jazzy Christmas - excellent trumpet playing
2. Another excellent trumpet album for the season is by Tine Thing Helseth, My heart is ever present
3. Kurt Elling kicks off the 15 songs album Blue Christmas, a Blue note selection
4. Nana Mouskouri's The Christmas Album has many well known songs with a twist as well as a few sung in French, German and Greek
5. Hot Club Cool Yule, Hot club of San Francisco
6. Have yourself a soulful little Christmas, Kenny Burrell
7 Six string Santa, Joe Pass
8. Let it swing: A Jazz Christmas with Verve
9. An Oscar Peterson Christmas
On the more religious side:
1. Catholic Latin Classics - Richard Proulx and the Cathedral Singers
2. Advent at Ephesus - Benedictines of Mary
3. On Yoolis Night - Anonymous 4
4. A Baroque Christmas - Boston Camerata
5. Veni Emmanuel - Classical Academic Press, all in Latin and all the better for that
6. Christmas Music from Medieval and Renaissance Europe - Sixteen and Harry Christophers
7. A Boston Camerata Christmas - Worlds of early Christmas Music
And a couple of different strings albums:
1. Christmas - Ustad Amjad Ali Khan, on the Indian Sarod. Christmas music on an Indian instrument, by a Muslim maestro, can't get more diverse or secular than that!
2. John Fahey's Christmas Album
If anyone has any new and unusual music for the holidays, please write about it here:-).